[GHC] #7338: Duplicate type signature not reported

[GHC]

#7338: Duplicate type signature not reported
-------------------------------------------------------------+--------------
 Reporter:  evincarofautumn                                  |          Owner:          
     Type:  bug                                              |         Status:  new     
 Priority:  normal                                           |      Component:  Compiler
  Version:  7.4.1                                            |       Keywords:          
       Os:  MacOS X                                          |   Architecture:  x86     
  Failure:  GHC accepts invalid program                      |       Testcase:          
Blockedby:                                                   |       Blocking:          
  Related:  http://hackage.haskell.org/trac/ghc/ticket/5589  |  
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 Under 7.4.1, the following snippet compiles without error:

 {{{
 a, a :: Int
 a = 0
 }}}

 It should issue the usual “duplicate type signature” diagnostic.

 [http://hackage.haskell.org/trac/ghc/changeset/82cd019e0ccf9c097e54b80cc94401863ee98ecd
 82cd019e] is probably relevant here.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7338>
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